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[en] Steel is a very versatile metallic material and widely used in modern life. Unfortunately, this material is prone to the phenomenon of corrosion and over time, can contribute to the failure of the product. In order to minimize this process, different types of coatings are used, due to their efficiency, economy and ease of application. The degradation of the film applied to steel by atmospheric agents is the result of the combination of various environmental factors, due to the highly destructive cyclic variations. The present work intends to determine the existence of significant statistical differences in the thickness distribution of coating in duplex systems (Fe/Zn/Paint), before and after conducting the humidity and temperature test with condensation in a constant atmosphere, from different tests carried out in the Stat graphics Centurion software. The influence of the preset conditions on the coating thickness before and after the test was demonstrated was demonstrated. These values were found in a suitable interval to guarantee the resistance to corrosion, not showing visible deterioration in the surface of the analyzed specimens.
[es]El acero es un material metálico muy versátil y ampliamente utilizado en la vida moderna. Desafortunadamente, este material está propenso al fenómeno de la corrosión y el pasar del tiempo, puede contribuir a la falla del producto. Para lograr minimizar este proceso se utilizan diferentes tipos de recubrimientos, debido a su eficacia, economía y facilidad de aplicación. La degradación de la película aplicada sobre el acero por los agentes atmosféricos es resultado de la combinación de diversos factores ambientales, debido a las variaciones cíclicas altamente destructivas. El presente trabajo pretende determinar la existencia de diferencias estadísticas significativas en las distribuciones del espesor de recubrimiento en sistemas dúplex (Fe/Zn/Pintura), antes y después de realizado el ensayo de humedad y temperatura con condensación en atmósfera constante, a partir de diferentes pruebas realizadas en el software Statgraphics Centurion. Se demostró la influencia de las condiciones prefijadas sobre el espesor de recubrimiento antes y después de realizado el ensayo. Dichos valores se encontraron en un intervalo adecuado para garantizar la resistencia a la corrosión, no evidenciándose deterioro visible en la superficie de las probetas analizadas.
[en] The article presents the results of analysis of statistical regularities (average seasonal and annual variations) of the changes in the total ozone, nitrogen oxide and water vapor in atmosphere, which were obtained during measurements at the AERONET station. It is shown that the dynamics of investigated greenhouse gases strongly depends on conditions of their generation and runoff, including meteorological and anthropogenic factors. (author)
[en] The article presents the results of analysis of statistical regularities (average daily and monthly variations) of changes in total ozone, nitrogen oxide and water vapor in the atmosphere, which were obtained during measurements at AERONET station. It is shown that dynamics of investigated greenhouse gases strongly depends on conditions of their generation and runoff, including meteorological and anthropogenic factors.
[en] The aim of this study was to find a model able to extract the net time per unit of net worked area from different agricultural field basic shapes (square, circle, rectangle and triangle) considering the following variables: field gross area, working speed, number of turnings (these depending on the effective working width), side length parallel and orthogonal to working direction, and working direction type. Being this a non-linear problem, an approach based on artificial neural networks is proposed. The model was trained using an artificial dataset calculated for the various shapes (internal test) and then tested on 47 different agricultural operations extracted by a real field dataset for the estimation of the net time (external test). The net time records obtained from both, the trained model and the external test, were correlated and the performance parameter r was extracted. Both regression coefficients (r), for the training and internal test, appear to be excellent being equal to 0.98 with respect to traditional linear approach (0.13). The variable “number of turnings” scored the highest impact, with a value equal to 44.34% for the net time estimation. Finally, the r correlation parameter for the external test resulted to be very high (0.80). This information is very valuable of the use of information management system for precision agriculture.
[en] The state of Rio Grande do Norte is a leader in wind power generation in the country with more than 150 wind farms in operation and 4 GW of installed capacity. Although the wind energy industry continues to grow, there are still very few papers that analyze wind behavior at heights above 80 m, which is typically the height of a wind turbine rotor. In this paper, a 95 m wind behavior analysis was carried out in two wind farms in the city of Parazinho-RN on monthly, seasonal and hourly scale, with the goal of identifying which periods of 2017 were more favorable for wind power production in the region. The wind speed and direction data used in this study were collected by a Thies First Class high precision cup anemometer and a Thies Compact wind direction indicator, corresponding to the hourly average of the measurements performed every second and integrated in intervals of 10 minutes in the period from January 1 to December 31, 2017. According with the results presented in this paper, it was verified that spring is the season of 2017 that presents the highest average monthly wind speeds, with maximum peak in the month of September, while lower speeds vary during the March-April-May quarter. The diurnal period between 10:00 am and 5:00 pm local time is the one with the most frequently wind speed ≥ 10 m.s-1. Wind direction varies from east to south, with predominance of east and southeast directions, in about 80% of the time. During the quarters that correspond to summer and fall, Weibull distributions are more concentrated around 6.5 and 7 m.s-1, indicating that in this period of the year there is a greater probability of occurrence of lower average speeds, implying in lower productivity for wind energy. The opposite is observed in winter and spring, with the exception of June, where the distributions are more concentrated around speeds ≥ 8 m.s-1 and there is a higher probability of higher average speeds to occur, showing that this was the best period of the year 2017 for wind power generation. (author)
[en] A device-independent dimension test for a Bell experiment aims to estimate the underlying Hilbert space dimension that is required to produce given measurement statistical data without any other assumptions concerning the quantum apparatus. Previous work mostly deals with the two-party version of this problem. In this paper, we propose a very general and robust approach to test the dimension of any subsystem in a multiparty Bell experiment. Our dimension test stems from the study of a new multiparty scenario which we call prepare-and-distribute. This is like the prepare-and-measure scenario, but the quantum state is sent to multiple, noncommunicating parties. Through specific examples, we show that our test results can be tight. Furthermore, we compare the performance of our test to results based on known bipartite tests, and witness remarkable advantages, which indicates that our test is of a true multiparty nature. We conclude by pointing out that with some partial information about the quantum states involved in the experiment, it is possible to learn other interesting properties beyond dimension. (paper)
[en] This work shows significant variations in the values of 210Po in different analyzed Polish voivodeships. Statistical analysis of 210Po activity concentrations in honey samples showed significant differences between place of honey collecting, kind of honey and morphological structure of plants from which bees collected nectar. (author)
[en] Cancer is proving to be a major concern in a worldwide context, particularly in underdeveloped countries. In 2005, out of a total of 58 million deaths worldwide, cancer was responsible for 7.6 million (13%). Of this total, more than 70% occurred in low and middle income countries. Cancer is currently the second leading cause of death in Brazil (10.3% of the total), excluding undetermined causes, behind only cardiovascular diseases. For 2018, there are an estimated 16,370 new cases, 2,300 of which are in the northern region of the country. Uterine cervix cancer is the second most frequent type of cancer among women worldwide. However, its frequency is variable according to the development of the country studied, and 83% of the cases recorded in the world occur in developing countries, where the cumulative risk is 1.5% at age 65. This study is a descriptive, retrospective, quantitative-interpretative study, with analysis of secondary data from the period from 2000 to 2015 of the Hospital Cancer Registry by the Health Information System (SIS-RHC), linked to the Regional Hospital of Araguaína. The data was tabulated in Excel electronic spreadsheets where statistical variables and frequencies were obtained for further analysis. A total of 2.664 women with cervical cancer were analyzed at the Regional Hospital of Araguaína. Being divided into 17 variables in the Tumor Form, the history of alcohol intake and tobacco presented the highest percentages of lack of completion (more than 31%). Subsequently, 25.9% did not contain schooling levels. In general, it can be noted that of the 17 references used in this study, 55.7% of the forms contained all the information and 12.2% had 4 or more missing data. It can be observed between the time of diagnosis and treatment that women diagnosed late presented. On overage, longer times between both actions. Most patients had a late diagnosis, with that , radiotherapy become the main form of treatment. (author)
[en] Objective: To build a model to evaluate the impact of salvage radiotherapy (SRT) in men with PSA rise or persistent PSA after undergoing radical prostatectomy (RP). Materials and Methods: The study included 107 node-negative patients treated with SRT after RP at a single institution. Patients received SRT for either prostate-specific antigen (PSA) rising, or PSA persistence after RP. All patients received local radiation to the prostate / seminal vesicle bed. The primary measured outcome was the biochemical recurrence (BCR) free survival. Multivariable Cox regression analysis was used to develop a risk-stratification group to identify predictive factors associated with the probability of BCR at 5yr. Results: At a median follow-up of 52 months, the BCR free survival rate and overall survival in 5 years was 73% and 94%, respectively. At multivariable analysis, pre-SRT PSA level > 0.35ng / mL (p = 0.023), negative margins (p = 0.038), and seminal vesicles invasion (p = 0.001) were significantly associated with BCR free survival. Three risk groups using regression analysis for SRT administration was built. Low-, intermediate and the high-risk groups had a BCR free survival in 5-years of 96%, 84%, and 44% (p = 0.0001), respectively. Conclusions: We developed a risk group stratification to show the impact of SRT based on prostate cancer characteristics. SRT showed to be extremely beneficial for patients with low- and intermediate-risk tumors. Moreover, the risk-group built could identify patients classified as high-risk who might benefit from more aggressive treatment for SRT. (author)
[en] Approximately 68.000 prostate cancer cases are estimated per year in Brazil, but many of these will present a bad prognosis due to the difficulties of access by users of public health services and the precariousness of many of these. This scenario is determinant for the occurrence of many cases of advanced disease, late diagnosis, worse clinical condition and higher risk of death. The state of Tocantins has a humble health structure that unfortunately does not yet have brachytherapy treatment for this condition and offers few beds for surgical treatment, while radiotherapy, performed in only one city in the state, coexists with constant problems and interruptions of care. The objective of this study is to analyze the population of patients with prostate cancer treated at the General Public Hospital of Palmas, the main state reference, in the year 2015, and specifically to determine how many of the patients could have been treated through brachytherapy. After approval by the Ethics and Research Committee, data collection, analysis, organization and treatment were carried out using BioEstat® statistical software, aiming at consolidating information, producing results and obtaining answers to the objectives of this study. The study demonstrated that the majority of these patients came from other localities, with advanced clinical staging, adenocarcinoma histological type, but with 19% of cases presenting criteria for treatment by brachytherapy, which would lead to a significant decrease in the demand for beds and referrals to other centers. (author)